The present invention relates to a method for manufacturing components such as heat exchangers, heat absorbers, rocket engines or the like.
According to German Pat. No. 1 751 691, rocket engines are known which consist substantially of a base structure or an inside wall of highly conducting material, especially copper, into which longitudinally extending cooling canals are milled which are covered by an outer wall, likewise of highly conductive material, especially copper, by means of electroplating. This is done in such a manner that, after the cooling canals are milled, the latter are filled with a wax which is superficially made electrically conducting, the outer wall is then electroplated on and the wax is subsequently melted out.
It has, however, been found in practice that melting out the filler material is not without problems inasmuch as the wax, when heated, expands more than the base material, whereby a deformation and formation of cracks can come about between the base structure and the electroplated-on copper layer.
In order to avoid this danger, it is further known from DE-OS No. 33 15 407, to place relatively thin plastic ropes into the longitudinally extending cooling canals before the latter are filled with wax, the ends of which protrude from the cooling canals. Before the wax is melted out, these plastic ropes are removed by pulling them out, whereby cavities are obtained in the wax filling, into which the wax can expand when it is warmed up, without stressing the rocket engine structure by pressure.
DE-OS No. 30 11 282 furthermore describes a method for manufacturing heat absorbers, the cover layer of which, produced by electroplating, is provided with convex raises above the cooling canal so that the expansions caused from the side of the cover layer during the operation as the consequence of direct heat absorption can be taken up more advantageously.
The known methods for the design and production of such wall structures, especially for removing the filling for the cooling canal, are either accompanied by danger for the safety of the wall structure or are time-consuming and economically expensive. It is therefore an object of the invention to propose a method and a filler for the cooling canal which can be used in carrying out the method which assures electroplating of the cover layer on the base structure without problems as well as an easy and reliable removal of the cooling canal filling and which is at the same time simple to handle from an installation point of view, and also technically economical.